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In this study, a new method of fabricating a composite frequency selective surface (FSS) using an e‐beam evaporator is proposed. The FSS is designed and fabricated as a part of the structure surface. A new concept of FSSs integrated into a composite skin structure provides a design that is electrically and structurally effective. This manufacturing process has the advantage of direct application of FSS function in a real structural surface with varied conformal skin. The multilayered FSSs of the patch‐grid‐patch type consist of a copper layer as a capacitive or inductive surface on a glass/epoxy pre‐impregnated (prepreg) substrate. The copper layer forming the FSS is manufactured using the e‐beam deposition on a glass/epoxy prepreg. The bandwidth of the designed FSS increases three times. The difference between the simulated and the measured results is due to the different evanescent wave interactions between the capacitive layers and inductive layer such as the local misalignment of the patch and grid, size of the specimen, and change in the thickness of the dielectric substrate after the manufacturing process. The bandwidth is successfully modified by correcting the design parameters such as the period, patch gap, grid width, and dielectric thickness. The band‐pass filtering and skirt characteristics appear in the experimental results, which agree well with the simulated results. This method is remarkably simple, and the manufactured FSS can function as both a structural skin and an FSS. Moreover, it has the merit of manufacturing simplicity and realization of structural shape. [ABSTRACT FROM AUTHOR]

The modular structure has a discontinuity owing to the joint between the modules; thus, structural behavior verification is required. In this study, the tensile behavior of a steel reinforcement at the discontinuity interface was evaluated in the joint of a modular flexural member. The modular specimen was fabricated with a 400 mm joint, and an integral specimen was fabricated with the same specifications as the modular specimen, without a joint. The largest crack width of the integral specimen was measured at the center of the beam, and that of the modular specimen was measured at the discontinuity interface. The maximum crack width of the modular specimen was greater than that of the integral specimen. The strain of the steel reinforcement was estimated using the measured crack width and six formulas for evaluating the crack width. The estimated strain of the modular specimen was higher than that of the integral specimen, and the deformation of the steel reinforcement at the discontinuity interface was accelerated with the increasing load. Therefore, the tensile load was concentrated at the discontinuity interface in the modular specimen, and the steel reinforcement at the discontinuity interface was likely to yield earlier than the integral specimen. [ABSTRACT FROM AUTHOR]